Field of the Invention
The invention relates to a folding-box gluing or adhesive-bonding machine for producing folding boxes from blanks. The machine includes a folding station at which parts of the blank parts, which have been provided with a strip of adhesive, are folded. An adjoining transfer station has at least two pairs of conveyor belts as a conveying device respectively including an upper and a lower belt. A device is provided for removing or ejecting faulty folding boxes. The removing device includes a circular knife for cutting in a conveying direction of the folding boxes and is mounted at a starting location of the transfer station so as to be lowerable between the two pairs of conveyor belts into a conveying plane of the folding boxes, and liftable from the conveying plane. A device is disposed on respective elongated sides of the transfer station for laterally withdrawing side parts of the blanks severed by the longitudinal cut. A collecting and pressing device presses the boxes, which have been folded flat, for effecting a setting of the adhesive.
The removing device in the transfer station serves for removing boxes detected as being faulty upstream from the collecting and pressing device, before an overlapping stream of the boxes is produced at the start of the collecting and pressing device. Due to the transfer station, the boxes continue to be conveyed individually and at a spaced distance from one another, so that an individual box can be pulled out or withdrawn without any detrimental effect upon the preceding and succeeding boxes. Faulty boxes are boxes which are not adequately glued or adhesively bonded, boxes which contain folding faults or boxes which, during an identity check, have been detected as not belonging to the job.
A removal device of that general type for separating out flat objects under control has become known heretofore from German Patent DE 41 29 612 C2. The device described therein has a marking station, wherein the folding boxes are automatically displaced laterally. The folding boxes are then disposed so as to overlap one another, and conveyed onwardly. The folding boxes which have been displaced laterally by the marker project laterally beyond the overlapping stream and are gripped by a rotary table and rollers running thereon and are torn from the overlapping stream, without disrupting the remaining overlapping stream.
In German Published, Non-Prosecuted Patent Application DE 199 48 017 A1, a folding-box gluing machine is described which includes a folding station, an adjacent transfer station and a collecting and pressing device. The transfer station has a removal device including a circular knife for cutting up the faulty folding boxes and a device for withdrawing or pulling out the folding-box parts. The circular knife is mounted at the start of the transfer station so as to be lowerable between the two pairs of conveyor belts into the conveying plane of the folding boxes, and liftable from the plane. The folding boxes can be divided in the conveying direction with the aid of the circular knife. A device which is disposed on each long side of the transfer station, for withdrawing or pulling out laterally the side parts severed by the longitudinal cut, is also included. Each of the pull-out or withdrawal devices has a belt conveyor, which extends from outside through a cutout in the upper roller rail to as far as the vicinity of the conveyor belt. The conveying direction of each belt conveyor runs outwardly inclined approximately at an angle of 45xc2x0 opposite to the conveying direction of the pairs of belts above a smooth table, which is fixed to the outside of the roller cheek or frame. The front deflection roller of the belt conveyor can be raised and lowered by a pneumatic piston-cylinder unit. When the deflection roller is lowered onto a folding-box part projecting outwardly beyond the conveyor belts, the belt draws or pulls the folding-box part outwardly over the table and removes it from the machine.
Heretofore known devices for withdrawing or pulling out, i.e., ejecting, with which a folding box is withdrawn or pulled out to one side between the pairs of conveyor belts, cannot be used when pressure rollers are employed for large box widths or, as belt conveyors, can only exert forces of insufficient strength on the folding boxes.
It is accordingly an object of the invention to provide a folding-box gluing or adhesive-bonding machine with an ejector or removal device, which overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and in which folding boxes detected as being faulty can be gripped reliably and removed at high speed.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a folding-box gluing or adhesive-bonding machine for producing folding boxes from blanks. The machine comprises a folding station at which parts of the blanks that have been provided with a strip of adhesive, are folded. An adjoining transfer station has at least two pairs of conveyor belts as a conveying device, respectively including an upper and a lower belt. A device for removing or ejecting faulty folding boxes includes a circular knife for cutting in a longitudinal conveying direction of the folding boxes and is mounted, at a starting location of the transfer station, so as to be lowerable between the two pairs of conveyor belts into a conveying plane of the folding boxes, and liftable from the conveying plane. A device is disposed on respective long sides of the transfer station for laterally withdrawing side parts of the blanks severed by the longitudinal cut. A collecting and pressing device presses the boxes, which have been folded flat, for setting the adhesive. The device for laterally withdrawing the severed side parts further includes a flat rotary table continuously revolvable at high speed. The rotary table is disposed outside and immediately adjacent one of the pairs of conveyor belts. An electric motor drives the rotary table. At least two pressure disks are disposed after one another, in running direction of the folding box blanks, downstream from the center of the rotary table and at an outer rim of the rotary table.
In accordance with another feature of the invention, the pressure disks are provided with a toothing in the form of gear wheels.
In accordance with a further feature of the invention, the machine further includes a two-sided lever at respective ends of which the pressure disks are freely rotatably mounted. The two-sided lever is tiltably fixed centrally.
In accordance with an added feature of the invention, the machine further includes a stop for adjusting spacing between the rotary table and the pressure disks.
In accordance with an additional feature of the invention, the machine further includes another circular knife respectively disposed inside adjacent the pairs of conveyor belts.
In accordance with yet another feature of the invention, the circular knife is freely rotatably mounted.
In accordance with yet a further feature of the invention, the machine further includes a housing wherein the circular knife is liftably and lowerably mounted. The housing is fixed to a lateral roller rail of the transfer station.
In accordance with yet an added feature of the invention, the housing is at least one of adjustable vertically and swivelable outwardly over the roller rail.
In accordance with yet an additional feature of the invention, the machine further includes one of a pot-shaped knife and a roller opposing the circular knife. The circular knife is movable downwardly against the one of the pot-shaped knife and the opposing roller for cutting, so as to produce a shearing cut.
In accordance with a concomitant feature of the invention, the machine includes guide plates respectively disposed inside and adjacent the pairs of conveyor belts. The guide plates are swivellable into a path of movement of the severed side parts and, in the running direction of the folding-box blanks, are aligned obliquely outwardly.
The object of the invention is thus achieved by the device for withdrawing or pulling out laterally the severed side parts, which includes a flat rotary table revolvable continuously at high speed, driven by an electric motor, and disposed immediately adjacent the conveyor belts, and at least two pressure disks which, in the running direction, are disposed one after another downstream of the center and at the outer rim of the rotary table. Placing a circular knife at the start of the transfer station and the device for withdrawing or pulling out laterally by a rotary table in the center of the transfer station, provide for gripping the divided folding boxes reliably, and withdrawing or pulling them out at high speed between the pairs of belts.
In a particularly advantageous configuration according to the invention, wherein the pressure disks are constructed as flat gear wheels, the reliability of gripping the folding-box parts is again increased. The use of a toothed disk also offers the advantage that a form-locking connection is produced between the toothed disks and the folding-box parts. Due to the form-locking connection, the folding-box parts are forced in one direction. By setting the distance between the rotary table and the flat gear wheels, the form-locking connection can be adapted individually to the respective thickness of the folding-box materials, and therefore the tensile force, when withdrawing or pulling out the folding-box parts, can be influenced. The tensile force produced via the form-locking connection of the flat gear wheels is, however, always greater, in this regard, than a force-locking connection between the pairs of conveyor belts.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a folding-box gluing or adhesive-bonding machine with an ejector device, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.